The most powerful cosmic explosions: supernovae and gamma-ray bursts.
The study of supernovae (SN) is directly connected to some of the most important fields in modern astrophysics, such as stellar evolution and cosmology. Gamma-ray bursts (GRB) allow the study of physical phenomena in extreme conditions and can also be used as probes of the distant Universe. The correlation between their spectral properties and their emitted energy could lead to their use as standard candles, to study the expansion of the Universe in an alternative and complementary way to type Ia SNe. In addition, both SN and GRB are, and above all will be fundamental for the study of neutrinos and gravitational waves.
Italian research
Type I supernovae: the results from recent years that have involved INAF researchers have provided elements for the understanding of the wide range of observed spectroscopic and photometric properties, and have demonstrated that about 90% of type Ia progenitors have similar masses at the time of explosion. Core-collapse supernovae: for the theoretical study of these objects, a code has been developed that demonstrates the existence of a continuum of properties between the least energetic objects (e.g. SN 1997D) and the most energetic (e.g. SN 1983K). The existence of "ultra-faint" core collapse SNe could have important implications for the study of "silent" GRBs. Association of supernovae with gamma-ray bursts: contrary to what was thought, not all long GRBs are associated with SNe, or at least not with SNe with absolute magnitudes typical of type Ic SNe. On the other hand, GRB 060218 has provided the clearest evidence of the association GRB/SN, and has allowed the system to be observed from birth. The event called GRB 080109 has been interpreted both as pure SN emission (with associated shock break out) and as an under-luminous GRB. Gamma-ray bursts: various Italian groups, both INAF and INFN, belong to research groups connected to Swift, AGILE and Fermi. There is also a significant theoretical contribution in the field of cosmology with GRBs, on emission mechanisms, on the interpretation of short GRBs and on the GRB/SN connection. Programmes have also been initiated to construct a catalogue of all the GRBs detected by INTEGRAL.
There are a great many instruments that can be used in the future in this field. ESO's ELT (European Extremely Large Telescope), the upgraded LVD (Large Volume Detector), the light GRB Monitor, the already mentioned CTA (Cherenkov Telescope Array) and the future satellites EUCLID, SVOM and Jaunus.
